1. Field of the Invention
Generally, the present invention relates to toy tops, gyroscopes and other rotating novelty devices. More particularly, the present invention relates to rotating novelty devices that contain internal electric motors that are periodically powered by a separate electric source that is remote to the rotating novelty device.
2. Description of the Prior Art
Tops, gyroscopes and other freely rotating devices share certain common functional features. Tops, gyroscopes and other rotating devices have a central axis around which they spin. The center of gravity associated with the rotating device passes through that central axis and the mass of the rotating device is evenly distributed around the central axis. As the top, gyroscope or similar device is put into motion, the device spins about its central axis. Since the mass of the rotating device is evenly distributed around the central axis, the device spins in a uniform manner, thereby enabling the device to be balanced at a point in line with the central axis. The device will spin in a stable manner until the rotational speed of the device falls below a certain threshold level. As the speed of the device decreases, its angular momentum decreases. Eventually, the presence of angular momentum is insufficient to overcome the forces of gravity and the rotating device tips over.
Tops, gyroscopes and other rotating novelty devices have been in existence for generations. During that period of time, there have been many variations in design of the rotating novelty devices. In their simplest form, rotating novelty devices, such as tops and gyroscopes, are either directly manually spun or manually spun using a pull cord that is wound around the rotating novelty device. Such manual means to provide rotational energy are inexpensive, however the rotational energy provided is relatively small. Consequently, the top or gyroscope would only rotate for a short period of time before they tip over.
The longer a top, gyroscope or other freely rotating device spins, the more play value it generally has. Consequently, in the prior art, attempts have been made to create tops, gyroscopes and other freely rotating devices that spin for extended periods of time. One popular method of creating a device that spins for a prolonged period of time is to place a motor within the structure of the device. The motor spins a weight, thereby producing the angular momentum needed to maintain a spinning motion for as long as the motor is powered.
In the prior art, such devices are typically created by placing an electric motor in the center of the top or other freely rotating device. Batteries are then symmetrically placed around the electric motor so as to be balanced around the center of rotation. The batteries typically serve as the majority of the weight that is spun. As a result, the batteries both provide power to the electric motor and add significantly to the angular momentum of the device. Such prior art devices are exemplified by U.S. Pat. No. 3,628,285, to Murakami, entitled Gyroscopic Top Device.
A problem associated with prior art tops and gyroscopes that contain internal motors and batteries is that great care must be taken in the manufacturing tolerances in order to maintain the proper balance. This raises the cost associated with manufacturing such devices. Furthermore, since the spinning object contains both an electric motor and batteries, the device is rather heavy. Such devices, therefore, have a tendency to become damaged if the commonplace happens and the device falls to the floor after spinning off a table edge or falls out of a child's hand.
A need therefore exists for an improved type of drive system for a spinning top, gyroscope or other freely rotating device that provides rotational energy to the device, yet does not require that batteries be contained within the rotating device. This need is met by the present invention as described and claimed below.